85 F250 starter relay problems
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85 F250 starter relay problems
1985 F250 manual 4WD 6 cylinder, PU used only for plowing a couple driveways, and summer yard work for past few years.
When I try to start the truck I get a chattering sound from the starter relay. I checked the battery and it is fully charged. But sometimes it starts just fine.
Seems like this has happened a couple times in the past I have replaced the starter relay every year or two. Is it just because I don't use the truck much anymore, or is it poor replacement parts, or does someone have an idea of what might be causing the problem?
Thanks
When I try to start the truck I get a chattering sound from the starter relay. I checked the battery and it is fully charged. But sometimes it starts just fine.
Seems like this has happened a couple times in the past I have replaced the starter relay every year or two. Is it just because I don't use the truck much anymore, or is it poor replacement parts, or does someone have an idea of what might be causing the problem?
Thanks
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From: Virginia
A low or bad battery will cause this(you checked this, so it's ok). Also bad battery cables will cause this. Corrosion on the battery terminal ends or hidden corrosion inside the cable end. Loose at the solenoid, or loose ground cable on the engine block.
What is happening is, with no load, the voltage rises up to 12 volts in the truck's elec system. When you turn the key, the solenoid is a small load, and pulls in. As soon as it pulls in, it applies the very large load of the starter on the battery and the cables. If there is a problem with the battery or the cable/cable connections, the voltage drops down in the system.
This robs the solenoid of voltage, so it drops out. When it drops out, the starter load is taken off the system, and the voltage rises again. Since you are still holding the key to start, the voltage rises up enough for the solenoid to kick back in. As soon as it kicks back in, the large starter load is applied, the voltage drops, the solenoid drops out, and the whole cycle starts over again. It does this very rapidly, and that is the buzzing or constant clicking you are hearing.
What is happening is, with no load, the voltage rises up to 12 volts in the truck's elec system. When you turn the key, the solenoid is a small load, and pulls in. As soon as it pulls in, it applies the very large load of the starter on the battery and the cables. If there is a problem with the battery or the cable/cable connections, the voltage drops down in the system.
This robs the solenoid of voltage, so it drops out. When it drops out, the starter load is taken off the system, and the voltage rises again. Since you are still holding the key to start, the voltage rises up enough for the solenoid to kick back in. As soon as it kicks back in, the large starter load is applied, the voltage drops, the solenoid drops out, and the whole cycle starts over again. It does this very rapidly, and that is the buzzing or constant clicking you are hearing.
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Thanks for the reply Franklin2,
I rechecked the battery which seemed fine, got the backhoe and jumped to the truck battery, and this time nothing. Disconnected the cable and shorted around the starter relay, and nothing. Took out the starter and jumped it direct to battery and nothing. Funny thing is it was working fine until that chattering started. Now have to wait until I make a town run to have the starter checked.
I am confused about one thing you said, "the solenoid drops out, and the whole cycle starts over again. It does this very rapidly, and that is the buzzing or constant clicking you are hearing." I had someone do the starting and it was not the solenoid on the starter that was clicking, all the noise was coming from the starter relay. Can you clarify? Thanks again for your help.
I rechecked the battery which seemed fine, got the backhoe and jumped to the truck battery, and this time nothing. Disconnected the cable and shorted around the starter relay, and nothing. Took out the starter and jumped it direct to battery and nothing. Funny thing is it was working fine until that chattering started. Now have to wait until I make a town run to have the starter checked.
I am confused about one thing you said, "the solenoid drops out, and the whole cycle starts over again. It does this very rapidly, and that is the buzzing or constant clicking you are hearing." I had someone do the starting and it was not the solenoid on the starter that was clicking, all the noise was coming from the starter relay. Can you clarify? Thanks again for your help.
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From: Virginia
The correct term as you used it for the firewall or fender piece is "relay". People commonly use the term "solenoid" and "relay" as meaning the same thing, though technically they are different. I was using both terms with one in parentheses so everyone could follow what I was saying, but I noticed most people described the relay on the fenderwell a "solenoid", so I just started using that instead of relay.
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